Alkylene bis (phenoxyacetic acid) derivatives as herbicides

ABSTRACT

Herbicides and insecticides of the formula   WHERE N IS 0, 1 OR 2, X and Y are halogen or hydrogen, R2 is hydrogen or methyl and R3 is methyl or trihalomethyl are provided.

United States Patent Alvin Guttag Bethesda, Md.

Dec. 19, 1968 Dec. 28, 1971 Weston Chemical Corporation New York, N.Y.

[72] inventor [21 Appl. No. [22] Filed [45] Patented [73] Assignee [54]ALKYLENE BIS (PHENOXYACETIC ACID) DERIVATIVES AS HERBICIDES 8 Claims, NoDrawings s21 U.S. c1 71/109, 71/88,71/116,424/131,424/134,424/151,

2,541,003 2/1951 Day et a1 260/520 FOREIGN PATENTS 1,404,919 5/1965France 260/473 OTHER REFERENCES Godt, Jr. et a1., Derivatives of 4,4-isopropy1idenebis, (2,6-dichlorophenol) 1967, CA 66, No. 115386K (1967)Trojna et a1., Some New Derivatives ofBfifl-trichloroa,a-bis(4-hydroxpheny1)ethane CA51 p. 11297 (1957)Primary Examiner-Lewis Gotts Assistant ExaminerG. HollrahAttorney-Cushman, Darby & Cushman ABSTRACT: Herbicides and inseetieidesof the formula x" Y Y' X nooc cmo OCHgC O 011 where n is 0, 1 or 2, Xand Y are halogen or hydrogen, R, is hydrogen or methyl and R, is methylor trihalomethyl are pr0- vided.

ALKYLENE BIS (PHENOXYACETIC ACID) DERIVATIVES AS HERBICIDES Thisinvention relates to new compounds which have herbicide-insecticideproperties. More particularly, the invention relates to novel Bisphenoxy acetic acid compounds and derivatives thereof which areselective herbicides and in some cases also are insecticides.

Many herbicides are known to the art and vary in activity toward avariety of plants in both preand post-emergence applications. A widelyused herbicide is 2,4-D(2,4- dichlorophenoxyacetic acid) and the saltsand esters thereof. 2,4-D is very effective at low concentrations onmost broadleafed plants and relatively ineffective on narrow-leafedplants. Also, 2,4-D is very effective as a postemergence herbicide andrelatively less effective as a preemergence herbicide. Accordingly,2,4-D has found wide application as an agricultural herbicide since itcan be applied to large fields in a rather noncritical manner foreffective weed control.

However, 2,4-D is not particularly selective in effect and almost allbroad-leafed and even some seminarrow and narrowleafed plants areaffected thereby, especially at higher application rates. Also, 2,4-D isquite stable and will persist for extended periods of time. Under thecircumstances, 2,4-D must be restricted in use with a large number ofcrops, notably among which are tomatoes and cotton. Further, grass weedssuch as setaria, Johnson grass, oats and wheat cannot be controlled by2,4-D and these are, of course, particularly troublesome weeds in manycrop fields, such as tomato and cotton fields. Also, since 2,4-Dpersists for extended time periods, a field that has been treated with2,4-D for control of broad-leafed plants cannot be safely usedimmediately, subsequent to the harvesting of a first crop, as a fieldfor growing a second broad-leafed crop, e.g. tomatoes and cotton.

A number of herbicides have been made which exhibit more selectivitythan 2,4-D and which will function only as a preemergence orpostemergence herbicide. These herbicides, however, only partially solvethe problems associated with the use of 2,4-D in that they are notsufficiently herbicidal and are not sufficiently selective and/or arepresent too long to allow the planting of subsequent crops, as notedabove, without fear of insufficient weed control or damage to the cropbeing treated or to subsequent crops planted.

Accordingly, it is an object of the present invention to provideherbicides which are quite selective and will not persist for extendedperiods and hence will not unduly retard the growing of crops in laterseasons. Another object is to develop herbicides which function only asa postemergence herbicide. It is further object to provide herbicideswhich are also insecticides and will control weeds and insects commonlyfound in many crop fields. Yet another object is to develop novelinsecticides. Other objects will be apparent from the followingdisclosure and claims.

Broadly stated the compounds of the present invention are the acids ofthe formulas l C l R IIOOCCH O OCH COOII the alkyl, alkoxyalkyl and arylesters thereof and the alkali metal, alkaline earth metal and aminesalts thereof, where X is halogen, e.g. chlorine, bromine, fluorine, nis 0, l or 2 and Y is halogen or hydrogen, R is hydrogen or methyl and Ris methyl or trihalomethyl.

Depending upon the value of n (the number of Xs), whether Y is halogenor hydrogen and the substituents R and R the compounds have differentproperties and utilities. Hence when R, and R are methyl and n is 2, thecompounds are herbicides. However, when R, is hydrogen or methyl, R, istrihalomethyl and n is 2, the compounds are both herbicidal andinsecticidal. But when R is hydrogen, or methyl, R is trihalomethyl andn is 0 or I, the compounds are only insecticidal.

Hence the acid form of the herbicides has the formula:

The acid form of the herbicides-insecticides has the formula:

X Y Y X 2 X HOOCCILO 1 +OCIIgC0OlI ix. X X

The acid form of the insecticides has the formula:

where R Y and X are as above.

Of course where Y is hydrogen the acid form of the insecticides willhave the formula:

I HOOCCH O C OCII COOH 6X3 As noted above, the compounds may be in theform of the esters and salts as well as the acids and the generalformulas will then be X Y X Y R1OOCCII2O OOIIgCOOR] R3 X X where R is H,alkyl, aryl, amino, alkali metal and alkaline earth metal. R, may be anester-forming group such as straight or branched or halogenated alkyl ofup to 20 carbon atoms, e.g. methyl, ethyl, propyl, hexyl, butyl, amyl,octyl, decyl, dodecyl, hexadecyl, octadecyl, isopropyl, isohexyl,isodecyl, 2-ethyl hexyl, chloromethyl, chlorohexyl, chlorododecyl,bromoisohexyl, bromododecyl and fluoroethyl or their secondary formssuch as isobutyl, isopropyl, isooctyl or mixed esters thereof. Or theester-forming group may be phenyl or halo substituted phenyl such asmonochlorophenyl, dichlorophenyl, monobromo and dibromo andfluorophenyl, straight or branched chain alkyl phenyl with up to 18carbon atoms in the alkyl chain such as methyl phenyl, ethyl phenyl,hexyl phenyl and octyl phenyl. The more convenient forms of the estersare the methyl, ethyl, propyl, butyl, amyl, octyl, decyl, (or thesecondary forms thereof, e.g. isobutyl, isopropyl, isooctyl),

butoxyethyl, propylene glycol butyl, 2-ethylhexyl, butoxypropyl, 3-(Z-butoxyethoxy) propyl, tert-octyl, tetrahydrofurfury] esters. Alsoconvenient are the straight chain glycol esters, e.g. propylene glycolbutyl ether ester, dipropylene glycol esters and butoxy ethoxy propanolester. R may also be a salt-forming group such as an alkali metal oralkali earth metal, e.g. sodium, potassium, lithium, cesium, magnesium,calcium, and barium. The salt-forming group may be an ammonium salt oran amine, where the amine used is of the formula:

where R R and R may be the same or different and are suitably hydrogen,alkyl of up to 18 carbon atoms, aryl or halo substituted alkyl of up to18 carbon atoms or halo substituted aryl or alkaryl of up to 18 carbonatoms in the alkyl chain, e.g. methyl, ethyl, propyl, butyl, hexyl,decyl, dodecyl, octadecyl, isopropyl, isodecyl, isooctadecyl, phenyl,chloro or bromo phenyl, dichloro or dibromo phenyl, p-methyl phenyl,o-ethyl phenyl, m-hexyl phenyl and p-octylphenyl. For example suitableamines (including ammonia) are the alkanolamines such as diandtrimethylamine, diand triethylamine, isopropylamine, dibutyl amine,diand triethanolamines, isopropanolamine, methyl phenyl amine, dimethylphenyl amine, diphenyl amine and triphenyl amine.

Examples of compound (2) are: 4,4'-isopropylidene bis(2,6-dichlorophenoxyacetic acid), 4,4-isopropylidene bis(2,6-dichlorophenoxy sodiumacetate), 4,4'-isopropylidene bis(2,6-dichlorophenoxy potassiumacetate), 4,4'-isopropylidene bis(2,6-dichlorophenoxy ethylacetate), 4,4-isopropylidene bis(2,6-dichlorophenoxy butylacetate), 4,4'-isopropylidene bis(2,6-dichlorophenoxy isooctylacetate), 4,4-isopropylidene bis(2,6-dibromophenoxy phenylacetate), 4,4'- isopropylidene bis(2,5-dibromophenoxy isodecylacetate), 4,4-isopropylidene bis(3,5-dichlorophenoxy ammonium acetate), 4,4'-isopropylidene bis(3,6-difiuorophenoxy acetic acid), 4-(2,6-dichlorophenoxymethylacetate)-4'-(2,6- dichlorophenoxy phenylacetate), propylidene4,2-isopropylidene bis (2,6-dichlorophenoxyacetic acid),3,3'-isopropylidene bis (2,5-dibromophenoxy methyl acetate), 4,4-isopropylidene bis (2,5-dichlorophenoxy triethylamine acetate),4,4-isopropylidene bis (2,3,6-trichlorophenoxy isooctyl acetate),4,4'-isopropylidene bis (2,6- dichlorophenoxy calcium acetate),4,4'-isopropylidene bis (2,6-dichlorophenoxy butoxyethyl acetate),4,4'-isopropylidene bis (2,5-dichlorophenoxy 2-chl0roethyl acetate),4,4- isopropylidene bis (2,5-dichlorophenoxy 4-chlorophenyl acetate),4,4-isopropylidene bis (2,6-dichlorophenoxy octadecyl acetate),4,4'-isopropylidene bis (2,6- dichlorophenoxy oleyl acetate),4,4-isopropylidene bis (2,6- dichlorophenoxy allyl acetate I The samecompounds noted above will serve to exemplify the compounds of formulas(3), (4), (5) and (6) except that the compounds are, of course, thel,l,l-trihalo ethylidene compounds, and in connection with formula 4 thephenoxy nucleus is of course mono or di halo substituted and inconnection with formula (5) is monosubstituted or unsubstituted byhalogen as shown by formula (6), e.g. 4,4'-l,1,ltrichloroethylidene bis(2,6-dichlorophenoxy acetic acid) (and the corresponding sodium andtriethanolamine salts) 4,4-l,l,1-trichloroethylidene bis(2-chlorophenoxy acetic acid), and 4,4-l,l,l-trichloroethylidene bis(phenoxy acetic acid), 4,4-1 ,1,l-trichloroethylidene bis (phenoxyacetic acid), and the corresponding above-noted esters and salts, e.g.,4,4'-1,1,l-trichloroethylidene bis (phenoxy isooctylacetate).

The compounds of the invention may be prepared in several fashions.Thus, two moles (plus a slight excess, e.g. up to percent) ofchloroacetic acid are reacted with 1 mole of (a) The acid may in turn bereacted with alkali metal, alkali metal hydroxide, an alkali earthmetal, an alkaline earth metal hydroxide, an amine, R -,R NH or analcohol R OH to produce the salt, amine salt or ester, respectively,where R, and R are as above and R, is alkyl or aryl or alkoxyalkyl asdefined above in connection with the esters of the present compounds.

Alternately, the alkali metal salts of both the chloroacetic acid andthe tetrahalo bisphenol may be reacted in the same manner. The freedibasic acid is then obtained by simply acidifying the suspension of thealkali metal salt produced with a mineral acid, e.g. HCl H 80 or theester is made by reacting the alkali metal salt with an alcohol.

Furthermore, the products may be produced by reacting 2 1 moles of ahalo phenol with 1 mole of a halo aldehyde and this i produce reactedwith chloroacetic acid, both reactions are preferably carried out in asolvent. This reaction is illustrated below in connection with 2,6dichlorophenol and chloral:

By treating the above acid with R,OH, R R NH or the salt forming groupas disclosed above, the ester, amine salt or salt is obtained.

Alternately, the ketone may be used in the reaction according to thatshown below:

Cl OH:

01 CH3 l 2,6,2,6'-tetrachloro bisphenol A Or, if desired, theunsubstituted phenol may be used in the i above reaction to producebisphenol A, which may be in turn rendered molten and reacted withchlorine gas, in the known manner, to provide a mixture of thechlorine-substituted isomers, the main isomer being the 2,6-isomer.Alternately, the phenol may be first chlorinated by rendering the phenolmolten and reacting with chlorine gas. The products so produced will bea mixture of isomers, but the main isomers are the 2,4 and 2,6-isomers.If desired, catalysts, e.g. FeCl AlCl and Sbcl may be used along with asolvent, e.g. CCl acetic acid and water, in carrying out the reaction,but this is not necessary.

The herbicides and herbicide-insecticides of the invention may beformulated into compositions which may be powders, dusts, granularproducts, liquids solutions, dispersions or pastes. The liquid can bewater or organic solvents, e.g.

kerosene, benzene, xylene, diesel oil, fuel oil, petroleum naphtha,perchloro ethylene, butyl acetate, etc.

The active substances may be put up in dry form, impregnated on inertcarriers for dust application, as dry powders, or in solid form, as inblocks or bars, pellets, granules, cakes or dry fertilizer mixes. Thedry forms may be diluted with inert dry carriers, for example, talc, ormay be diluted in water for spray application. Wetting agents anddispersing agents may be added to the dry forms as required, oralternately, wetting agents may be added to the liquid forms.

The compositions, formulated as above, are usually diluted for thepurposes of application to the crops and applied to the locus to betreated at a rate in the range offrom about 2 oz. to about 20 pounds ofthe total active substance by weight of the ingredients of thecomposition per acre. While the preferred liquid diluent is water, thesolid diluent may be as desired, e.g. dirt, talc, fullers earth,fertilizer, bentonite, lime, etc.

' Generally the active ingredients are diluted to a weight percent ofactive ingredients of from 1 percent to 50 percent although as little as0.00001 percent or only the active ingredient itself may be used ifdesired. The compounds can be employed as aerosols, e.g. by dispersingthem in air by means of a compressed gas such asdichlorodifluoromethane.

Typical wetting agents include sodium alkyl benzene sulfonates having 10to 18 carbon atoms in the alkyl group, pisooctylphenol-IO ethylene oxideadduct, sodium lignin sulfonate, sodium lauryl sulfate and sodiumstearate.

Alternately an alkali metal salt of isopropylidene diphenol, ahalohydrin and an alkali metal salt ofa halo acetic acid may be reactedand the free acid obtained by treatment with a strong acid. This willproduce the halo unsubstituted acid which may be subsequentlyhalogenated as noted above.

The compounds, use and methods of producing the com pounds of theinvention will be illustrated by the following examples where all partsare by weight unless otherwise noted. However, it should be understoodthat the invention is not limited to the specific examples butapplicable to the extent of the foregoing disclosure.

EXAMPLE 1 Preparation of 4,4'-lSOPROPYLlDENE BlS (2,6-

DlCHLQROPHENOXYACETlC ACID) (:1 (win o noocclno O --0cuio0ou or 011.1 c1

The disodium salt of 4,4'-isopropylidene bis (2,6- dichlorophenoxyaceticacid) was prepared by reacting the disodium salt of tetrachlorobisphenolA in aqueous solution with the sodium salt of chloroacetic acid inaqueous solution.

The free dibasic acid was obtained on acidification of an aqueoussuspension of the disodium salt. The details of the reaction are asfollows:

SOLUTION A 1,500 ml. Water 366 g. Tetruchlorobisphenol I Mole] 83 g.Sodium hydroxide, Tech.

(2 Mole, NaOH) 2 g. Potassium Iodide Solution A was heated to refluxtemperature until all solids were dissolved. it was stirred andmaintained at 98-l00 C. while cold solutions, B, C, and D respectivelyof sodium chloroacetate were added. Solutions B, C, and D weremaintained below 40 C. at all times, both during preparation and use.

SOLUTION B [,000 ml. Water 200 g. chloroacetic acid (2 Moles 5 86 g.Sodium Hydroxide (Tech. Fluke) One hour was required for the addition ofSolution B. The resulting reaction mixture was then heated at 9496 C.for an additional 50 minutes.

SOLUTION C 250 ml. Water 50 g. Chloroucetic acid 2] g. Sodium HydroxideSolution C was added in 15 minutes and the reaction mixture heated at94+-96 C. for 1 hour.

SOLU'llON D 125 ml. Water 30 g. chloroacetic acid 13 g. Sodium HydroxideSolution D was added in 15 minutes. Heating was then continued for 30minutes, at which time solids began crystallizing. Heating was stoppedand stirring continued for 2 hours. The reaction mixture was allowed tostand overnight at room temperature, the solids then separated byfiltration and washed free of chloride ion. The dry solid produceweighed 426 g. for a yield of 78 percent of theory. The dry solidproduct was suspended in 2 liters of boiling water and then acidified byadding concentrated hydrochloric acid. The water insoluble oil whichseparated was washed free of chloride ion by small portions of hotwater. Molecular Weight, 482; Chlorine, 30.5 percent.

EXAMPLE 2 Preparation of THE DlBUTYL ESTER The 4,4-isopropylidene bis(2,6-Dichlorophenoxyacetic acid) prepared by the procedure ofexample 1,without further purification, was used to prepare the dibutyl ester andthe dimethylamine salt as follows:

DIBUTYL ESTER I g. Of the acid 400 g. n-Butanol 200 g. Toluene 2 Cone.sulfuric acid This mixture was heated to reflux temperature and 30 ml.water removed as an azeotrope using a sidearm. The product was thenwashed with three portions of hot water and finally stripped at 140 C.and 10 mm. pressure. 184 g. of viscous, light tan, product wasrecovered. Molecular Weight, 594; Chlorine, 24.3 percent.

EXAMPLE 6 The procedure of example was repeated with the amine salt,prepared as by example 3. The amine salt was dissolved in EXAMPLE 3water to provide an approximately 1.5 w/w percent solution.

, i I 7 Jhe results are shown in table l TABLE 1.POST EMERGENCEHERBICIDAL EVALUATION Dose, Pig J. M. Chemical lbs/acre weed Setariagrass glory Tomatoes Oats Wheat Cues. R.K.B. Cotton I 5 3 7 6 0 0 1 0 83 0 Dimethyl amine salt 2. 5 2 0 O 0 0 5 6 7 2 0 l 1. 0 ,0 0 0 0 4 4 1 00 5 3 2 2 5 3 l0 4 l) 9 3 Butyl 2. 5 3 0 0 3 0 8 2 7 5 U 1. 25 2 0 0 2 05 1 7 2 0 Karmex 2 10 9 7 6 7 6 6 10 10 3Y Check 0 0 0 0 0 0 0 0 0 0NOTE.-Y= yellowing.

DI-DIMETHYLAMINE SALT Of the acid Anhydrous dimethylamine 70 g. 200 ml.

, These reactants were thoroughly mixed at 5 C. and then allowed tostand overnight at 5 to 10 C. The solid which formed was finelypulverized in a mortar, cooled again to 5 C.

. and 50 g. liquid. Dimethylamine added and ground with the solid. Thefinely pulverized product was allowed to warm to room temperature andfreed of excess dimethylamine. The product weighed 79 g. Molecularweight, 572; Chlorine, 25.2 percent.

EXAMPLE 4 hours.

The reaction mixture is poured into water and the crystal- As is known,the normal response from 2,4-D would be to I have complete kill ofpigweed, morning glory, tomatoes, cu-.

cumbers, red kidney beans and cotton at the l.25 pound rate 5 atvariance with the 2,4-D pattern and therefore the compositions aresubstantially difierent in response than 2,4-D. The herbicidal effectis, however, very pronounced in wheat, oats and cucumbers. Cotton andtomatoes are perhaps among the most sensitive plants to 2,4-D but wereunaffected by the present compositions. The fact that cotton andtomatoes were unaffected by the amine salt and only slightly affected athigh doses of the ester shows that there is a completely differentbiological response with the present compositions as compared with the2,4-D materials.

Accordingly, the present compositions may be applied to growing cropssuch as tomatoes and cotton to rid the crops of common weeds withoutdanger of damage to the crops. Such line solids are recovered therefromby filtering. The solids are recrystallized from ether to obtain amixture of the position isomers of 4,4-l,l ,l-trichloroethylidene bis(2,6- dichlorophenol), i.e. (HOC H Cl CHCCl The so obtained bisphenolwas converted to the disodium salt and reacted according to theprocedure of example 1 with the sodium salt of chloroacetic acid toobtain the corresponding salt, i.e. the disodium salt' of4,4-l,l,l-trichloroethylidene bis (2,6- dichlorophenoxy acetic acid).This salt was then acidified with HCl to form the free dibasic acid. Theprocedure of example 1 and with the same mole ratios was used in thereaction and a mixture of the position isomers wasformed, butprincipally the product is the 4,4-l,l,1-trichloroethylidene bis (2,6-

dichlorophenoxy acetic acid) isomer.

The following examples demonstrate the herbicidal properties ofrepresentative compounds of the invention.

EXAMPLE 5 An approximately l.5 w/w percent dilution of the dibutylester, prepared as by example 2, was emulsified in an approximatelyequal mixture of Butyl Carbitol Acetate (diethylene glycol monobutylether acetate) and Velsicol solvent (aromatic petroleum solvents ofstraight chain structure which have been cyclized). The composition wasapplied to pigweed,

selectivity is of great importance especially when large fields ofgrowing crops must be weeded in relatively short times and underconditions which do not admit to carefully controlled placementplacement of the herbicide.

EXAMPLE 7 In order to illustrate the lack of preemergence activity ofthe present compounds, the same amine salt and butyl ester compositions,as described in examples 5 and 6, were used to drench the surface ofground having tomato and cotton seeds therein. Also a check" andreference selective herbicide, Karmex, were used to evaluate the presentcompositions, in a manner discussed in example 5. The results are shownin table 2 where G. stands for the percent of plants which germinatedand P.R. stands for the phytotoxicity. Note that the untreated plants ofthe check have an percent germination.

. TABL PREEMERGENCE HERBlClDAL EVALUATION can also be applied inagriculturaluses.

As can be seen from table 2, the present compositions do bound bytheory, it is believed that this result is obtained known horticulturalcarriers, such as kerosene, or similar light mineral oil distillates ofintermediate viscosity and volatility. Adjuvants, such as spreading orwetting agents, may be included in the solutions, such as fatty acidsoaps, rosin salts,

The concentration of the active ingredient to be used with the abovecarriers will be dependent upon many factors, such I as the carrier inor upon which it is incorporated, the method and conditions ofapplication, the insect species to be conbecause of the relatively greatrate of breakdown of the trolled, etc., the proper consideration ofthese factors being present compositions as compared with Karmex and2,4-D within the skill of those versed in the art. in general, the toxiccompounds which are relatively inert and resist decomposiingredients ofthis invention will be effective in concentrations tion for long times.from about 0.01 percent to about 0.5 percent by weight, based Hence afield could be weeded by applying the composiupon the total weight ofthe composition, although depending tions of the invention andthereafter tomatoes or cotton could upon the circumstances as little asabout 0.00001 percent or be planted without fear of inhibiting theirgermination and as much as 50 percent or even more of the activeingredient growth thereof. may be employed.

The compounds of formula 3 are also insecticides as well as Th toxiagents of this invention may be employed as the herbicides and thecompounds of formulas 4 and 5 are insectisole toxic ingredient of theinsecticidal composition or they cides for many insects, among which areincluded the commay be employed in conjunction with other insecticidallyacmon pests such as the Mexican bean beetle, cockroaches, flies 1 tivematerials. Such other insecticidally active materials in- (e.g. Muscadomestica) and mosquito larvae. By the term in- 1 elude, without beinglimited to, the naturally occurring insecsect it is intended to includenot only the members of the class ticides, such as pyrethrum, rotenone,sabadilla, and the like, as lnsecta but also related or similarnonvertebrate animal organwell as synthetic materials such as compoundsof arsenic, lead, isms belonging to allied classes of arthropods andincluding and/or fluorine; DDT, benzene hexachloride, thiodiphen mites,ticks, spiders, wood lice, and the like. ylamine, cyanides, tetraethylpyrophosphate, 0,0-diethyl-O-p- For employing the compounds of theinvention in combatnitrophenyl thiophosphate, azobenzene, and the like.ing insects and similar pests there can be employed the usual Generallyspeaking the topical LD for insects is less than procedures familiar tothose skilled in the art. For example, I 500 mg./kg., e.g. 1 to 400 andespecially 1 to 50 mg./kg. and the agents may be sprayed or otherwiseapplied in the form of good kills are obtained with dosages within theseranges. solutions or dispersions, or adsorbed on inert finely divided MA solids and applied as dusts. Solutions of the novel insecticidesEXAMPLE 8 suitable for application by spraying, brushing, dipping, orthe like can be prepared using as the solvent any of the well- Thecompounds shown below in table 3 are applied by dusting at the dosagesshown to Musca domestica. The kills are rated at 0 through 4, where 0 isless than 10 percent kills, 1 is less than 30 percent kills, 2 is lessthan percent kills, 3 is v less than jt) percent kills and 4 is 7 0percent kills and above.

TABLE 3 Kill rating at specified dosages in mg/kg.

Compound 500 400 100 50 1. 4,4-1,1,l-trichloroisoethylidene bis(2,6-dichlorophenoxy acetic acid) 4 4 4 3 2.4,4-1,1.l-trichloroisoethylidene bis (3,Chi0l'OPi'l8DOXY acetic acid)..4 4 3 3 3. 4,4-1,1,l-trichloroisoethylidene bis (3,6-phen0xy aceticacid) r 4 4 3 3 4. 4.4-1,1,1-trichloroethylidene bis(3,5,6-dichlorophen0xv acetic acid). 4 4 4 4 5.4,4-1,Ll-trichloroethylidene bis (2-bromophenoxy acetic acid). 4 4 3 36. 4,4-1,LI-trichloroethylidene bis (2,5-bromophen0xy acetic acid) 4 4 33 saponins, gelatin, casein, or other proteinaceous material, orsynthetic wetting agents of the type of sulfates of long-chain fattyalcohols, alkyl aryl sulfonates, long-chain alkyl sulfonates,phenol-ethylene oxide condensates, C to C amines and ammonium salts, andthe like. The solution may be.

dispersed or emulsified in water and the resulting dispersion oremulsion applied as the spray. Solid carrier materials which can beemployed include talc, bentonite, lime, gypsum, pyrophyllite, and thelike inert solid diluents. The compounds also may be applied asaerosols, as by dispersing them into the air by means of a compressedgas. The more volatile of the 89"99111? new? Plays? as i e v lmhsy.

The compounds of the invention have the advantage over DDT of notremaining for long periods of time after an area has been sprayed.

EXAMPLES 9 THROUGH 22 To further illustrate the compounds of the presentinvention example I is repeated except that the tetrachlorobisphenol Awas replaced in the same mole amount with the compounds set forth intable 4 and the bis chlorophenoxy acetic acid products obtained had thephysical form noted below in table 4. The compounds of examples 9through 15 were converted Startingccmpound to thediethyl amine salt andshowed herbicidal activity similar TABLE 4 Product Vlcosc Liquid SolidLiquid s s-I P a e- -trichloroeth -trichloroethylidene bis(2,5,6-hexachlor0pheno -trichloroethylidenc bis (3,5-tetrachlorophenol)-t1'lchloroethylidene bis (2,3-tctrachlorophenol) -tn'chlor0ethylidenebis (2,3,fi-hexachlorophenol) 2,5,2,5-tetrachlorobisphenol A X 62,5,6-hexachlorobisphenol A. ,5-tetrachlorobisphen0l A.,3-tetrachlorobisphenol A. 2,3,5-hexachlorobisphen0l A,6-tetrachl0robisphenol A.

ylidene bis (2,5-tetrachlorophenbl5 have only a low volatility and henceare less effective when employed in this manner. The toxic agents of theinvention to that of the amine salt of example 6. The compounds ofexamples 16 through 22 showed insecticidal activity toward it {r sendomestica similar to that of example 8.

What is claimed:

1. A process for the selective control of weeds comprising applying toweeds at a rate equivalent to 2 oz. to 20 lbs. per acre of a herbicidewhich is a post emergent, selective her- I bicidal compositioncontaining an efiective amount of at least qk s alsqmp ev efihmlas X Y XY HOOCCHQO CI OCH COOH CH3 X X X Y X Y I'IOOCOHQO (ll- OCHQCOOII X X (B)and the alkali metal, alkaline earth metal and ammonium or amine saltsthereof where the salt-forming amine is of the for- I mula R R NR and RR and R, may be the same or different and selected from hydrogen, alkyl,hydrocarbyl alkaryl and hydrocarbyl aryl, or halo alkyl, hydrocarbylhaloalkaryl and hydrocarbyl haloaryl all of which may be up to 18 carbonatoms; and the alkyl, alkoxyalkyl or haloalkyl esters thereof whereinthe alkyl group is up to 20 carbon atoms; and the phenyl, halophenyl oralkyl phenyl esters thereof wherein the alkyl group is up to l8 carbonatoms; and where X is halogen and Y is'halogen or hydrogen; theremaining portion of the composition being selected from at least one ofinert diluents 1 or carriers and wetting agents.

2. A process according to claim 1 wherein the herbicidal composition isapplied to weeds in the presence of tomato 3. A process according toclaim 1 wherein the herbicidal composition is applied to weeds in thepresence of cotton plants.

4. The process according to claim 1 wherein R R and R are alkylorhaloalkyl of up to 18 carbon atoms, phenyl, halophenyl or lower alkylphenyl, and wherein the said ester is alkyl, alkoxyalkyl or haloalkyl ofup to 20 carbon atoms, monoor di-halo phenyl and lower alkyl phenyl.

5. The process of claim 1 wherein the herbicidal compound '10 is one ofthe said esters and the esters are phenyl, halo-substituted phenyl, andalkyl substituted phenyl of up to 18 carbon atoms in the alkyl chain.

6. The process of claim 1 where the herbicidal compound is one of thesaid amine salts and the amine salts are salts of amiaesstfthef tmfiwhere R R and R may be the same or different and are hydrogen, alkylof up to 18 carbon atoms, aryl, halo-substituted alkyl of up to 18carbon atoms, halo-substituted aryl

2. A process according to claim 1 wherein the herbicidal composition isapplied to weeds in the presence of tomato plants.
 3. A processaccording to claim 1 wherein the herbicidal composition is applied toweeds in the presence of cotton plants.
 4. The process according toclaim 1 wherein R4, R5 and R6 are alkyl or haloalkyl of up to 18 carbonatoms, phenyl, halophenyl or lower alkyl phenyl, and wherein the saidester is alkyl, alkoxyalkyl or haloalkyl of up to 20 carbon atoms, mono-or di-halo phenyl and lower alkyl phenyl.
 5. The process of claim 1wherein the herbicidal compound is one of the said esters and the estersare phenyl, halo-substituted phenyl, and alkyl substituted phenyl of upto 18 carbon atoms in the alkyl chain.
 6. The process of claim 1 wherethe herbicidal compound is one of the said amine salts and the aminesalts are salts of amines of the formula where R4, R5 and R6 may be thesame or different and are hydrogen, alkyl of up to 18 carbon atoms,aryl, halo-substituted alkyl of up to 18 carbon atoms, halo-substitutedaryl and alkaryl of up to 18 carbon atoms in the alkyl chain.
 7. Theprocess of claim 1 wherein the herbicidal compound is of formula (A). 8.The process of claim 1 wherein the herbicidal compound is one of thesaid salts or esters of the acid selected from the group consisting of4,4''-isopropylidene bis (2,5,6-trichlorophenoxy acetic acid),4,4''-isopropylidene bis (3,5,-dichlorophenoxy acetic acid),4,4''-isopropylidene bis (2,3-dichlorophenoxy acetic acid),4,4''-isopropylidene bis (2,3,5-trichlorophenoxy acetic acid),4,4''-isopropylidene bis (2,6-dichlorophenoxy acetic acid), and4,4''-isopropylidene bis (3,6-dichlorophenoxy acetic acid).